package com.yyc.controller;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.*;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class LoginC1Servlet extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
//response.setContentType("text/html;charset=UTF-8");
//PrintWriter out = response.getWriter();
String id =request.getParameter("id");
String password=request.getParameter("password");
//从数据库中获取验证
Connection con=null;
ResultSet rs=null;
PreparedStatement ps=null;
try{
//1.加载驱动
Class.forName("mysql.jdbc.Driver");
//2.得到链接
con = DriverManager.getConnection("jdbc:mysql://localhost:3306/itat_shop", "root", "chuan080702");
//3.preparedStatement
ps=con.prepareStatement("select *from users where id=? and passwd=?");
//给?号赋值
ps.setObject(1,id);
ps.setObject(2,password);
//4.执行操作
rs=ps.executeQuery();
//5.根据结果做相应的处理
if(rs.next()){
//说明该用户合法
request.getRequestDispatcher("/MainFrame").forward(request, response);
}else{
request.setAttribute("err", "用户id或密码错误！！！");
request.getRequestDispatcher("/LoginServlet").forward(request, response);
}
}catch(Exception e){
e.printStackTrace();
}finally{
//关闭资源
if(rs!=null){
try{
rs.close();
}catch(Exception e){
e.printStackTrace();
}
rs=null;
}
if(ps!=null){
try{
ps.close();
}catch(Exception e){
e.printStackTrace();
}
ps=null;
}if(con!=null){
} try{
con.close();
}catch(Exception e){
e.printStackTrace();
}
con=null;
}
/*
//检查是否接受数据
//这里我们先简单验证
if("yangyongchuan".equals(username)&&"123".equals(password)){
//跳转到下一个页面[servlet 提供了两种Sendredirect跳转forward 转发]
response.sendRedirect("/UserManager/MainFrame?uname="+username);
}else{
//跳回
response.sendRedirect("/UserManager/LoginServlet");
}
**/
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
this.doGet(request, response);
}
}
信息: Server startup in 14390 ms
java.lang.ClassNotFoundException: mysql.jdbc.Driver
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1680)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1526)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:190)
at com.yyc.controller.LoginC1Servlet.doGet(LoginC1Servlet.java:30)
at com.yyc.controller.LoginC1Servlet.doPost(LoginC1Servlet.java:112)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:643)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:879)
at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:617)
at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1778)
at java.lang.Thread.run(Thread.java:744)
java.lang.NullPointerException
at com.yyc.controller.LoginC1Servlet.doGet(LoginC1Servlet.java:79)
at com.yyc.controller.LoginC1Servlet.doPost(LoginC1Servlet.java:112)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:643)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:879)
at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:617)
at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1778)
at java.lang.Thread.run(Thread.java:744)
报的错在哪？把错误也贴出来。
啥错？报的错在哪？把错误也贴出来。
ava.lang.ClassNotFoundException: mysql.jdbc.Driver
加载驱动出错
你看看连接 mysql 的类加载驱动那一片代码。
下面的例子是可用的，当然用户名及密码每个人设置的不一样
public class DBO {
private static String driver = "com.mysql.jdbc.Driver";
private static String url = "jdbc:mysql://localhost:3306/mysql3";
private static String username = "root";
private static String password = "739150";
static{
try{
/**
* 加载驱动
*/
Class.forName(driver);
}catch(Exception ex){
ex.printStackTrace();}
}
public static Connection getConnection(){
/**
* 创建连接对象
*/
Connection conn = null;
try{
conn=DriverManager.getConnection(url,username,password);
}catch(Exception ex){
ex.printStackTrace();}
return conn;
}
/**
* 关闭流
* @param rs
* @param st
* @param conn
*/
public static void close(ResultSet rs,Statement st,Connection conn){
try {
if(rs!=null){
rs.close();
}
if(st!=null){
st.close();
}
if(conn!=null){
conn.close();
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static void close(PreparedStatement pst,Connection conn){
close(null,pst,conn);
}
}